drivers/mtd/mtdpart.c

   1 /*
   2  * Simple MTD partitioning layer
   3  *
   4  * Copyright © 2000 Nicolas Pitre <nico@fluxnic.net>
   5  * Copyright © 2002 Thomas Gleixner <gleixner@linutronix.de>
   6  * Copyright © 2000-2010 David Woodhouse <dwmw2@infradead.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21  *
  22  */
  23
  24 #include <linux/module.h>
  25 #include <linux/types.h>
  26 #include <linux/kernel.h>
  27 #include <linux/slab.h>
  28 #include <linux/list.h>
  29 #include <linux/kmod.h>
  30 #include <linux/mtd/mtd.h>
  31 #include <linux/mtd/partitions.h>
  32 #include <linux/err.h>
  33 #include <linux/kconfig.h>
  34
  35 #include "mtdcore.h"
  36
  37 /* Our partition linked list */
  38 static LIST_HEAD(mtd_partitions);
  39 static DEFINE_MUTEX(mtd_partitions_mutex);
  40
  41 /* Our partition node structure */
  42 struct mtd_part {
  43         struct mtd_info mtd;
  44         struct mtd_info *master;
  45         uint64_t offset;
  46         struct list_head list;
  47 };
  48
  49 /*
  50  * Given a pointer to the MTD object in the mtd_part structure, we can retrieve
  51  * the pointer to that structure.
  52  */
  53 static inline struct mtd_part *mtd_to_part(const struct mtd_info *mtd)
  54 {
  55         return container_of(mtd, struct mtd_part, mtd);
  56 }
  57
  58
  59 /*
  60  * MTD methods which simply translate the effective address and pass through
  61  * to the _real_ device.
  62  */
  63
  64 static int part_read(struct mtd_info *mtd, loff_t from, size_t len,
  65                 size_t *retlen, u_char *buf)
  66 {
  67         struct mtd_part *part = mtd_to_part(mtd);
  68         struct mtd_ecc_stats stats;
  69         int res;
  70
  71         stats = part->master->ecc_stats;
  72         res = part->master->_read(part->master, from + part->offset, len,
  73                                   retlen, buf);
  74         if (unlikely(mtd_is_eccerr(res)))
  75                 mtd->ecc_stats.failed +=
  76                         part->master->ecc_stats.failed - stats.failed;
  77         else
  78                 mtd->ecc_stats.corrected +=
  79                         part->master->ecc_stats.corrected - stats.corrected;
  80         return res;
  81 }
  82
  83 static int part_point(struct mtd_info *mtd, loff_t from, size_t len,
  84                 size_t *retlen, void **virt, resource_size_t *phys)
  85 {
  86         struct mtd_part *part = mtd_to_part(mtd);
  87
  88         return part->master->_point(part->master, from + part->offset, len,
  89                                     retlen, virt, phys);
  90 }
  91
  92 static int part_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
  93 {
  94         struct mtd_part *part = mtd_to_part(mtd);
  95
  96         return part->master->_unpoint(part->master, from + part->offset, len);
  97 }
  98
  99 static unsigned long part_get_unmapped_area(struct mtd_info *mtd,
 100                                             unsigned long len,
 101                                             unsigned long offset,
 102                                             unsigned long flags)
 103 {
 104         struct mtd_part *part = mtd_to_part(mtd);
 105
 106         offset += part->offset;
 107         return part->master->_get_unmapped_area(part->master, len, offset,
 108                                                 flags);
 109 }
 110
 111 static int part_read_oob(struct mtd_info *mtd, loff_t from,
 112                 struct mtd_oob_ops *ops)
 113 {
 114         struct mtd_part *part = mtd_to_part(mtd);
 115         int res;
 116
 117         if (from >= mtd->size)
 118                 return -EINVAL;
 119         if (ops->datbuf && from + ops->len > mtd->size)
 120                 return -EINVAL;
 121
 122         /*
 123          * If OOB is also requested, make sure that we do not read past the end
 124          * of this partition.
 125          */
 126         if (ops->oobbuf) {
 127                 size_t len, pages;
 128
 129                 len = mtd_oobavail(mtd, ops);
 130                 pages = mtd_div_by_ws(mtd->size, mtd);
 131                 pages -= mtd_div_by_ws(from, mtd);
 132                 if (ops->ooboffs + ops->ooblen > pages * len)
 133                         return -EINVAL;
 134         }
 135
 136         res = part->master->_read_oob(part->master, from + part->offset, ops);
 137         if (unlikely(res)) {
 138                 if (mtd_is_bitflip(res))
 139                         mtd->ecc_stats.corrected++;
 140                 if (mtd_is_eccerr(res))
 141                         mtd->ecc_stats.failed++;
 142         }
 143         return res;
 144 }
 145
 146 static int part_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
 147                 size_t len, size_t *retlen, u_char *buf)
 148 {
 149         struct mtd_part *part = mtd_to_part(mtd);
 150         return part->master->_read_user_prot_reg(part->master, from, len,
 151                                                  retlen, buf);
 152 }
 153
 154 static int part_get_user_prot_info(struct mtd_info *mtd, size_t len,
 155                                    size_t *retlen, struct otp_info *buf)
 156 {
 157         struct mtd_part *part = mtd_to_part(mtd);
 158         return part->master->_get_user_prot_info(part->master, len, retlen,
 159                                                  buf);
 160 }
 161
 162 static int part_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
 163                 size_t len, size_t *retlen, u_char *buf)
 164 {
 165         struct mtd_part *part = mtd_to_part(mtd);
 166         return part->master->_read_fact_prot_reg(part->master, from, len,
 167                                                  retlen, buf);
 168 }
 169
 170 static int part_get_fact_prot_info(struct mtd_info *mtd, size_t len,
 171                                    size_t *retlen, struct otp_info *buf)
 172 {
 173         struct mtd_part *part = mtd_to_part(mtd);
 174         return part->master->_get_fact_prot_info(part->master, len, retlen,
 175                                                  buf);
 176 }
 177
 178 static int part_write(struct mtd_info *mtd, loff_t to, size_t len,
 179                 size_t *retlen, const u_char *buf)
 180 {
 181         struct mtd_part *part = mtd_to_part(mtd);
 182         return part->master->_write(part->master, to + part->offset, len,
 183                                     retlen, buf);
 184 }
 185
 186 static int part_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
 187                 size_t *retlen, const u_char *buf)
 188 {
 189         struct mtd_part *part = mtd_to_part(mtd);
 190         return part->master->_panic_write(part->master, to + part->offset, len,
 191                                           retlen, buf);
 192 }
 193
 194 static int part_write_oob(struct mtd_info *mtd, loff_t to,
 195                 struct mtd_oob_ops *ops)
 196 {
 197         struct mtd_part *part = mtd_to_part(mtd);
 198
 199         if (to >= mtd->size)
 200                 return -EINVAL;
 201         if (ops->datbuf && to + ops->len > mtd->size)
 202                 return -EINVAL;
 203         return part->master->_write_oob(part->master, to + part->offset, ops);
 204 }
 205
 206 static int part_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
 207                 size_t len, size_t *retlen, u_char *buf)
 208 {
 209         struct mtd_part *part = mtd_to_part(mtd);
 210         return part->master->_write_user_prot_reg(part->master, from, len,
 211                                                   retlen, buf);
 212 }
 213
 214 static int part_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
 215                 size_t len)
 216 {
 217         struct mtd_part *part = mtd_to_part(mtd);
 218         return part->master->_lock_user_prot_reg(part->master, from, len);
 219 }
 220
 221 static int part_writev(struct mtd_info *mtd, const struct kvec *vecs,
 222                 unsigned long count, loff_t to, size_t *retlen)
 223 {
 224         struct mtd_part *part = mtd_to_part(mtd);
 225         return part->master->_writev(part->master, vecs, count,
 226                                      to + part->offset, retlen);
 227 }
 228
 229 static int part_erase(struct mtd_info *mtd, struct erase_info *instr)
 230 {
 231         struct mtd_part *part = mtd_to_part(mtd);
 232         int ret;
 233
 234         instr->addr += part->offset;
 235         ret = part->master->_erase(part->master, instr);
 236         if (ret) {
 237                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 238                         instr->fail_addr -= part->offset;
 239                 instr->addr -= part->offset;
 240         }
 241         return ret;
 242 }
 243
 244 void mtd_erase_callback(struct erase_info *instr)
 245 {
 246         if (instr->mtd->_erase == part_erase) {
 247                 struct mtd_part *part = mtd_to_part(instr->mtd);
 248
 249                 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
 250                         instr->fail_addr -= part->offset;
 251                 instr->addr -= part->offset;
 252         }
 253         if (instr->callback)
 254                 instr->callback(instr);
 255 }
 256 EXPORT_SYMBOL_GPL(mtd_erase_callback);
 257
 258 static int part_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 259 {
 260         struct mtd_part *part = mtd_to_part(mtd);
 261         return part->master->_lock(part->master, ofs + part->offset, len);
 262 }
 263
 264 static int part_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 265 {
 266         struct mtd_part *part = mtd_to_part(mtd);
 267         return part->master->_unlock(part->master, ofs + part->offset, len);
 268 }
 269
 270 static int part_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
 271 {
 272         struct mtd_part *part = mtd_to_part(mtd);
 273         return part->master->_is_locked(part->master, ofs + part->offset, len);
 274 }
 275
 276 static void part_sync(struct mtd_info *mtd)
 277 {
 278         struct mtd_part *part = mtd_to_part(mtd);
 279         part->master->_sync(part->master);
 280 }
 281
 282 static int part_suspend(struct mtd_info *mtd)
 283 {
 284         struct mtd_part *part = mtd_to_part(mtd);
 285         return part->master->_suspend(part->master);
 286 }
 287
 288 static void part_resume(struct mtd_info *mtd)
 289 {
 290         struct mtd_part *part = mtd_to_part(mtd);
 291         part->master->_resume(part->master);
 292 }
 293
 294 static int part_block_isreserved(struct mtd_info *mtd, loff_t ofs)
 295 {
 296         struct mtd_part *part = mtd_to_part(mtd);
 297         ofs += part->offset;
 298         return part->master->_block_isreserved(part->master, ofs);
 299 }
 300
 301 static int part_block_isbad(struct mtd_info *mtd, loff_t ofs)
 302 {
 303         struct mtd_part *part = mtd_to_part(mtd);
 304         ofs += part->offset;
 305         return part->master->_block_isbad(part->master, ofs);
 306 }
 307
 308 static int part_block_markbad(struct mtd_info *mtd, loff_t ofs)
 309 {
 310         struct mtd_part *part = mtd_to_part(mtd);
 311         int res;
 312
 313         ofs += part->offset;
 314         res = part->master->_block_markbad(part->master, ofs);
 315         if (!res)
 316                 mtd->ecc_stats.badblocks++;
 317         return res;
 318 }
 319
 320 static inline void free_partition(struct mtd_part *p)
 321 {
 322         kfree(p->mtd.name);
 323         kfree(p);
 324 }
 325
 326 /*
 327  * This function unregisters and destroy all slave MTD objects which are
 328  * attached to the given master MTD object.
 329  */
 330
 331 int del_mtd_partitions(struct mtd_info *master)
 332 {
 333         struct mtd_part *slave, *next;
 334         int ret, err = 0;
 335
 336         mutex_lock(&mtd_partitions_mutex);
 337         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 338                 if (slave->master == master) {
 339                         ret = del_mtd_device(&slave->mtd);
 340                         if (ret < 0) {
 341                                 err = ret;
 342                                 continue;
 343                         }
 344                         list_del(&slave->list);
 345                         free_partition(slave);
 346                 }
 347         mutex_unlock(&mtd_partitions_mutex);
 348
 349         return err;
 350 }
 351
 352 static struct mtd_part *allocate_partition(struct mtd_info *master,
 353                         const struct mtd_partition *part, int partno,
 354                         uint64_t cur_offset)
 355 {
 356         struct mtd_part *slave;
 357         char *name;
 358
 359         /* allocate the partition structure */
 360         slave = kzalloc(sizeof(*slave), GFP_KERNEL);
 361         name = kstrdup(part->name, GFP_KERNEL);
 362         if (!name || !slave) {
 363                 printk(KERN_ERR"memory allocation error while creating partitions for \"%s\"\n",
 364                        master->name);
 365                 kfree(name);
 366                 kfree(slave);
 367                 return ERR_PTR(-ENOMEM);
 368         }
 369
 370         /* set up the MTD object for this partition */
 371         slave->mtd.type = master->type;
 372         slave->mtd.flags = master->flags & ~part->mask_flags;
 373         slave->mtd.size = part->size;
 374         slave->mtd.writesize = master->writesize;
 375         slave->mtd.writebufsize = master->writebufsize;
 376         slave->mtd.oobsize = master->oobsize;
 377         slave->mtd.oobavail = master->oobavail;
 378         slave->mtd.subpage_sft = master->subpage_sft;
 379
 380         slave->mtd.name = name;
 381         slave->mtd.owner = master->owner;
 382
 383         /* NOTE: Historically, we didn't arrange MTDs as a tree out of
 384          * concern for showing the same data in multiple partitions.
 385          * However, it is very useful to have the master node present,
 386          * so the MTD_PARTITIONED_MASTER option allows that. The master
 387          * will have device nodes etc only if this is set, so make the
 388          * parent conditional on that option. Note, this is a way to
 389          * distinguish between the master and the partition in sysfs.
 390          */
 391         slave->mtd.dev.parent = IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER) ?
 392                                 &master->dev :
 393                                 master->dev.parent;
 394
 395         slave->mtd._read = part_read;
 396         slave->mtd._write = part_write;
 397
 398         if (master->_panic_write)
 399                 slave->mtd._panic_write = part_panic_write;
 400
 401         if (master->_point && master->_unpoint) {
 402                 slave->mtd._point = part_point;
 403                 slave->mtd._unpoint = part_unpoint;
 404         }
 405
 406         if (master->_get_unmapped_area)
 407                 slave->mtd._get_unmapped_area = part_get_unmapped_area;
 408         if (master->_read_oob)
 409                 slave->mtd._read_oob = part_read_oob;
 410         if (master->_write_oob)
 411                 slave->mtd._write_oob = part_write_oob;
 412         if (master->_read_user_prot_reg)
 413                 slave->mtd._read_user_prot_reg = part_read_user_prot_reg;
 414         if (master->_read_fact_prot_reg)
 415                 slave->mtd._read_fact_prot_reg = part_read_fact_prot_reg;
 416         if (master->_write_user_prot_reg)
 417                 slave->mtd._write_user_prot_reg = part_write_user_prot_reg;
 418         if (master->_lock_user_prot_reg)
 419                 slave->mtd._lock_user_prot_reg = part_lock_user_prot_reg;
 420         if (master->_get_user_prot_info)
 421                 slave->mtd._get_user_prot_info = part_get_user_prot_info;
 422         if (master->_get_fact_prot_info)
 423                 slave->mtd._get_fact_prot_info = part_get_fact_prot_info;
 424         if (master->_sync)
 425                 slave->mtd._sync = part_sync;
 426         if (!partno && !master->dev.class && master->_suspend &&
 427             master->_resume) {
 428                         slave->mtd._suspend = part_suspend;
 429                         slave->mtd._resume = part_resume;
 430         }
 431         if (master->_writev)
 432                 slave->mtd._writev = part_writev;
 433         if (master->_lock)
 434                 slave->mtd._lock = part_lock;
 435         if (master->_unlock)
 436                 slave->mtd._unlock = part_unlock;
 437         if (master->_is_locked)
 438                 slave->mtd._is_locked = part_is_locked;
 439         if (master->_block_isreserved)
 440                 slave->mtd._block_isreserved = part_block_isreserved;
 441         if (master->_block_isbad)
 442                 slave->mtd._block_isbad = part_block_isbad;
 443         if (master->_block_markbad)
 444                 slave->mtd._block_markbad = part_block_markbad;
 445         slave->mtd._erase = part_erase;
 446         slave->master = master;
 447         slave->offset = part->offset;
 448
 449         if (slave->offset == MTDPART_OFS_APPEND)
 450                 slave->offset = cur_offset;
 451         if (slave->offset == MTDPART_OFS_NXTBLK) {
 452                 slave->offset = cur_offset;
 453                 if (mtd_mod_by_eb(cur_offset, master) != 0) {
 454                         /* Round up to next erasesize */
 455                         slave->offset = (mtd_div_by_eb(cur_offset, master) + 1) * master->erasesize;
 456                         printk(KERN_NOTICE "Moving partition %d: "
 457                                "0x%012llx -> 0x%012llx\n", partno,
 458                                (unsigned long long)cur_offset, (unsigned long long)slave->offset);
 459                 }
 460         }
 461         if (slave->offset == MTDPART_OFS_RETAIN) {
 462                 slave->offset = cur_offset;
 463                 if (master->size - slave->offset >= slave->mtd.size) {
 464                         slave->mtd.size = master->size - slave->offset
 465                                                         - slave->mtd.size;
 466                 } else {
 467                         printk(KERN_ERR "mtd partition \"%s\" doesn't have enough space: %#llx < %#llx, disabled\n",
 468                                 part->name, master->size - slave->offset,
 469                                 slave->mtd.size);
 470                         /* register to preserve ordering */
 471                         goto out_register;
 472                 }
 473         }
 474         if (slave->mtd.size == MTDPART_SIZ_FULL)
 475                 slave->mtd.size = master->size - slave->offset;
 476
 477         printk(KERN_NOTICE "0x%012llx-0x%012llx : \"%s\"\n", (unsigned long long)slave->offset,
 478                 (unsigned long long)(slave->offset + slave->mtd.size), slave->mtd.name);
 479
 480         /* let's do some sanity checks */
 481         if (slave->offset >= master->size) {
 482                 /* let's register it anyway to preserve ordering */
 483                 slave->offset = 0;
 484                 slave->mtd.size = 0;
 485                 printk(KERN_ERR"mtd: partition \"%s\" is out of reach -- disabled\n",
 486                         part->name);
 487                 goto out_register;
 488         }
 489         if (slave->offset + slave->mtd.size > master->size) {
 490                 slave->mtd.size = master->size - slave->offset;
 491                 printk(KERN_WARNING"mtd: partition \"%s\" extends beyond the end of device \"%s\" -- size truncated to %#llx\n",
 492                         part->name, master->name, (unsigned long long)slave->mtd.size);
 493         }
 494         if (master->numeraseregions > 1) {
 495                 /* Deal with variable erase size stuff */
 496                 int i, max = master->numeraseregions;
 497                 u64 end = slave->offset + slave->mtd.size;
 498                 struct mtd_erase_region_info *regions = master->eraseregions;
 499
 500                 /* Find the first erase regions which is part of this
 501                  * partition. */
 502                 for (i = 0; i < max && regions[i].offset <= slave->offset; i++)
 503                         ;
 504                 /* The loop searched for the region _behind_ the first one */
 505                 if (i > 0)
 506                         i--;
 507
 508                 /* Pick biggest erasesize */
 509                 for (; i < max && regions[i].offset < end; i++) {
 510                         if (slave->mtd.erasesize < regions[i].erasesize) {
 511                                 slave->mtd.erasesize = regions[i].erasesize;
 512                         }
 513                 }
 514                 BUG_ON(slave->mtd.erasesize == 0);
 515         } else {
 516                 /* Single erase size */
 517                 slave->mtd.erasesize = master->erasesize;
 518         }
 519
 520         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 521             mtd_mod_by_eb(slave->offset, &slave->mtd)) {
 522                 /* Doesn't start on a boundary of major erase size */
 523                 /* FIXME: Let it be writable if it is on a boundary of
 524                  * _minor_ erase size though */
 525                 slave->mtd.flags &= ~MTD_WRITEABLE;
 526                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't start on an erase block boundary -- force read-only\n",
 527                         part->name);
 528         }
 529         if ((slave->mtd.flags & MTD_WRITEABLE) &&
 530             mtd_mod_by_eb(slave->mtd.size, &slave->mtd)) {
 531                 slave->mtd.flags &= ~MTD_WRITEABLE;
 532                 printk(KERN_WARNING"mtd: partition \"%s\" doesn't end on an erase block -- force read-only\n",
 533                         part->name);
 534         }
 535
 536         slave->mtd.ecclayout = master->ecclayout;
 537         slave->mtd.ecc_step_size = master->ecc_step_size;
 538         slave->mtd.ecc_strength = master->ecc_strength;
 539         slave->mtd.bitflip_threshold = master->bitflip_threshold;
 540
 541         if (master->_block_isbad) {
 542                 uint64_t offs = 0;
 543
 544                 while (offs < slave->mtd.size) {
 545                         if (mtd_block_isreserved(master, offs + slave->offset))
 546                                 slave->mtd.ecc_stats.bbtblocks++;
 547                         else if (mtd_block_isbad(master, offs + slave->offset))
 548                                 slave->mtd.ecc_stats.badblocks++;
 549                         offs += slave->mtd.erasesize;
 550                 }
 551         }
 552
 553 out_register:
 554         return slave;
 555 }
 556
 557 static ssize_t mtd_partition_offset_show(struct device *dev,
 558                 struct device_attribute *attr, char *buf)
 559 {
 560         struct mtd_info *mtd = dev_get_drvdata(dev);
 561         struct mtd_part *part = mtd_to_part(mtd);
 562         return snprintf(buf, PAGE_SIZE, "%lld\n", part->offset);
 563 }
 564
 565 static DEVICE_ATTR(offset, S_IRUGO, mtd_partition_offset_show, NULL);
 566
 567 static const struct attribute *mtd_partition_attrs[] = {
 568         &dev_attr_offset.attr,
 569         NULL
 570 };
 571
 572 static int mtd_add_partition_attrs(struct mtd_part *new)
 573 {
 574         int ret = sysfs_create_files(&new->mtd.dev.kobj, mtd_partition_attrs);
 575         if (ret)
 576                 printk(KERN_WARNING
 577                        "mtd: failed to create partition attrs, err=%d\n", ret);
 578         return ret;
 579 }
 580
 581 int mtd_add_partition(struct mtd_info *master, const char *name,
 582                       long long offset, long long length)
 583 {
 584         struct mtd_partition part;
 585         struct mtd_part *new;
 586         int ret = 0;
 587
 588         /* the direct offset is expected */
 589         if (offset == MTDPART_OFS_APPEND ||
 590             offset == MTDPART_OFS_NXTBLK)
 591                 return -EINVAL;
 592
 593         if (length == MTDPART_SIZ_FULL)
 594                 length = master->size - offset;
 595
 596         if (length <= 0)
 597                 return -EINVAL;
 598
 599         memset(&part, 0, sizeof(part));
 600         part.name = name;
 601         part.size = length;
 602         part.offset = offset;
 603
 604         new = allocate_partition(master, &part, -1, offset);
 605         if (IS_ERR(new))
 606                 return PTR_ERR(new);
 607
 608         mutex_lock(&mtd_partitions_mutex);
 609         list_add(&new->list, &mtd_partitions);
 610         mutex_unlock(&mtd_partitions_mutex);
 611
 612         add_mtd_device(&new->mtd);
 613
 614         mtd_add_partition_attrs(new);
 615
 616         return ret;
 617 }
 618 EXPORT_SYMBOL_GPL(mtd_add_partition);
 619
 620 int mtd_del_partition(struct mtd_info *master, int partno)
 621 {
 622         struct mtd_part *slave, *next;
 623         int ret = -EINVAL;
 624
 625         mutex_lock(&mtd_partitions_mutex);
 626         list_for_each_entry_safe(slave, next, &mtd_partitions, list)
 627                 if ((slave->master == master) &&
 628                     (slave->mtd.index == partno)) {
 629                         sysfs_remove_files(&slave->mtd.dev.kobj,
 630                                            mtd_partition_attrs);
 631                         ret = del_mtd_device(&slave->mtd);
 632                         if (ret < 0)
 633                                 break;
 634
 635                         list_del(&slave->list);
 636                         free_partition(slave);
 637                         break;
 638                 }
 639         mutex_unlock(&mtd_partitions_mutex);
 640
 641         return ret;
 642 }
 643 EXPORT_SYMBOL_GPL(mtd_del_partition);
 644
 645 /*
 646  * This function, given a master MTD object and a partition table, creates
 647  * and registers slave MTD objects which are bound to the master according to
 648  * the partition definitions.
 649  *
 650  * For historical reasons, this function's caller only registers the master
 651  * if the MTD_PARTITIONED_MASTER config option is set.
 652  */
 653
 654 int add_mtd_partitions(struct mtd_info *master,
 655                        const struct mtd_partition *parts,
 656                        int nbparts)
 657 {
 658         struct mtd_part *slave;
 659         uint64_t cur_offset = 0;
 660         int i;
 661
 662         printk(KERN_NOTICE "Creating %d MTD partitions on \"%s\":\n", nbparts, master->name);
 663
 664         for (i = 0; i < nbparts; i++) {
 665                 slave = allocate_partition(master, parts + i, i, cur_offset);
 666                 if (IS_ERR(slave)) {
 667                         del_mtd_partitions(master);
 668                         return PTR_ERR(slave);
 669                 }
 670
 671                 mutex_lock(&mtd_partitions_mutex);
 672                 list_add(&slave->list, &mtd_partitions);
 673                 mutex_unlock(&mtd_partitions_mutex);
 674
 675                 add_mtd_device(&slave->mtd);
 676                 mtd_add_partition_attrs(slave);
 677
 678                 cur_offset = slave->offset + slave->mtd.size;
 679         }
 680
 681         return 0;
 682 }
 683
 684 static DEFINE_SPINLOCK(part_parser_lock);
 685 static LIST_HEAD(part_parsers);
 686
 687 static struct mtd_part_parser *mtd_part_parser_get(const char *name)
 688 {
 689         struct mtd_part_parser *p, *ret = NULL;
 690
 691         spin_lock(&part_parser_lock);
 692
 693         list_for_each_entry(p, &part_parsers, list)
 694                 if (!strcmp(p->name, name) && try_module_get(p->owner)) {
 695                         ret = p;
 696                         break;
 697                 }
 698
 699         spin_unlock(&part_parser_lock);
 700
 701         return ret;
 702 }
 703
 704 static inline void mtd_part_parser_put(const struct mtd_part_parser *p)
 705 {
 706         module_put(p->owner);
 707 }
 708
 709 /*
 710  * Many partition parsers just expected the core to kfree() all their data in
 711  * one chunk. Do that by default.
 712  */
 713 static void mtd_part_parser_cleanup_default(const struct mtd_partition *pparts,
 714                                             int nr_parts)
 715 {
 716         kfree(pparts);
 717 }
 718
 719 int __register_mtd_parser(struct mtd_part_parser *p, struct module *owner)
 720 {
 721         p->owner = owner;
 722
 723         if (!p->cleanup)
 724                 p->cleanup = &mtd_part_parser_cleanup_default;
 725
 726         spin_lock(&part_parser_lock);
 727         list_add(&p->list, &part_parsers);
 728         spin_unlock(&part_parser_lock);
 729
 730         return 0;
 731 }
 732 EXPORT_SYMBOL_GPL(__register_mtd_parser);
 733
 734 void deregister_mtd_parser(struct mtd_part_parser *p)
 735 {
 736         spin_lock(&part_parser_lock);
 737         list_del(&p->list);
 738         spin_unlock(&part_parser_lock);
 739 }
 740 EXPORT_SYMBOL_GPL(deregister_mtd_parser);
 741
 742 /*
 743  * Do not forget to update 'parse_mtd_partitions()' kerneldoc comment if you
 744  * are changing this array!
 745  */
 746 static const char * const default_mtd_part_types[] = {
 747         "cmdlinepart",
 748         "ofpart",
 749         NULL
 750 };
 751
 752 /**
 753  * parse_mtd_partitions - parse MTD partitions
 754  * @master: the master partition (describes whole MTD device)
 755  * @types: names of partition parsers to try or %NULL
 756  * @pparts: info about partitions found is returned here
 757  * @data: MTD partition parser-specific data
 758  *
 759  * This function tries to find partition on MTD device @master. It uses MTD
 760  * partition parsers, specified in @types. However, if @types is %NULL, then
 761  * the default list of parsers is used. The default list contains only the
 762  * "cmdlinepart" and "ofpart" parsers ATM.
 763  * Note: If there are more then one parser in @types, the kernel only takes the
 764  * partitions parsed out by the first parser.
 765  *
 766  * This function may return:
 767  * o a negative error code in case of failure
 768  * o zero otherwise, and @pparts will describe the partitions, number of
 769  *   partitions, and the parser which parsed them. Caller must release
 770  *   resources with mtd_part_parser_cleanup() when finished with the returned
 771  *   data.
 772  */
 773 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
 774                          struct mtd_partitions *pparts,
 775                          struct mtd_part_parser_data *data)
 776 {
 777         struct mtd_part_parser *parser;
 778         int ret, err = 0;
 779
 780         if (!types)
 781                 types = default_mtd_part_types;
 782
 783         for ( ; *types; types++) {
 784                 pr_debug("%s: parsing partitions %s\n", master->name, *types);
 785                 parser = mtd_part_parser_get(*types);
 786                 if (!parser && !request_module("%s", *types))
 787                         parser = mtd_part_parser_get(*types);
 788                 pr_debug("%s: got parser %s\n", master->name,
 789                          parser ? parser->name : NULL);
 790                 if (!parser)
 791                         continue;
 792                 ret = (*parser->parse_fn)(master, &pparts->parts, data);
 793                 pr_debug("%s: parser %s: %i\n",
 794                          master->name, parser->name, ret);
 795                 if (ret > 0) {
 796                         printk(KERN_NOTICE "%d %s partitions found on MTD device %s\n",
 797                                ret, parser->name, master->name);
 798                         pparts->nr_parts = ret;
 799                         pparts->parser = parser;
 800                         return 0;
 801                 }
 802                 mtd_part_parser_put(parser);
 803                 /*
 804                  * Stash the first error we see; only report it if no parser
 805                  * succeeds
 806                  */
 807                 if (ret < 0 && !err)
 808                         err = ret;
 809         }
 810         return err;
 811 }
 812
 813 void mtd_part_parser_cleanup(struct mtd_partitions *parts)
 814 {
 815         const struct mtd_part_parser *parser;
 816
 817         if (!parts)
 818                 return;
 819
 820         parser = parts->parser;
 821         if (parser) {
 822                 if (parser->cleanup)
 823                         parser->cleanup(parts->parts, parts->nr_parts);
 824
 825                 mtd_part_parser_put(parser);
 826         }
 827 }
 828
 829 int mtd_is_partition(const struct mtd_info *mtd)
 830 {
 831         struct mtd_part *part;
 832         int ispart = 0;
 833
 834         mutex_lock(&mtd_partitions_mutex);
 835         list_for_each_entry(part, &mtd_partitions, list)
 836                 if (&part->mtd == mtd) {
 837                         ispart = 1;
 838                         break;
 839                 }
 840         mutex_unlock(&mtd_partitions_mutex);
 841
 842         return ispart;
 843 }
 844 EXPORT_SYMBOL_GPL(mtd_is_partition);
 845
 846 /* Returns the size of the entire flash chip */
 847 uint64_t mtd_get_device_size(const struct mtd_info *mtd)
 848 {
 849         if (!mtd_is_partition(mtd))
 850                 return mtd->size;
 851
 852         return mtd_to_part(mtd)->master->size;
 853 }
 854 EXPORT_SYMBOL_GPL(mtd_get_device_size);